An important aspect of writing code is handling indentation. When you properly indent, you make it easier to read on-screen. The Visual Studio Code Editor provides three indentation styles:

By default, the Code Editor indents each code line based on the standards for the programming language: smart indenting. When you're typing your code, the Editor automatically indents the line. When smart indentation is enabled, you can't manually increase indentation by pressing the Tab key.

To change the indentation style used by the Code Editor, follow these steps:

Figure 1-2. Set the indentation style for the Code Editor.

You can access formatting features to indent your code by choosing Edit

Some indentation and comment commands are available on the Text Editor toolbar, as shown in Figure 1-3.

Most of these commands are useless if you're using smart indentation. Smart indentation automatically manages indentation for you. You might choose to turn off smart indentation if your company uses a different indentation standard. Also, you might want to use your own indentation standard, such as using white spaces instead of tabs.

Figure 1-3. Use the Text Editor toolbar to increase indentation or comment out a selection.

Visual Studio provides extensive Find and Replace capabilities that go way beyond what you find in a standard text editor. Table 1-2 lists the Find and Replace options. You access the Find and Replace commands by choosing Edit

The Find and Replace commands all use the same dialog box, and most of the commands use the same options. As Figure 1-4 shows, your Find and Replace options are the following:

To select a different kind of Find and Replace command, open the drop-down lists displayed at the top of the Find and Replace dialog box.

The Find Symbols command restricts your search to only symbols. Symbols are the methods and type definitions declared in source code. You can use the Find Symbols command to search your own code or external libraries for which you don't have source code. The results of the Find Symbols code appear in the Find Symbol Results window. Figure 1-5 shows the results from a search for BeginSend in a set of source code. The results show exactly where BeginSend is used in source code. Double-click any of the results to go to the source code.

Figure 1-5. The Find Symbol Results window displays all the instances where the text appears in symbols.

Use the Visual Studio Task List to keep track of a simple list of to-do items. The Task List window displays two kinds of tasks:

The Task List provides a consolidated list of tasks you enter directly into the Task List window and tagged comments you place inside your source code. The default set of tags you use to mark your comments comprises TODO, HACK, or UNDONE.

To tag a comment within your source code, use the standard comment mark for your programming language, followed by one of the task comment tags. For example, to add a task comment in Visual Basic or C#, you type the following:

VB:

'todo Code review this

C#:

// todo Code review this

The Task List window consolidates all your task comments in a single view. You can double-click a comment in the Task List to jump to the location in the source code where the comment appears. To open the Task List window, click Task List on the View window. Figure 1-6 shows an example of the Task List window.

Figure 1-6. Task comments from source code appear in the Task List window.

You can add your own task comment tags. Figure 1-6 uses a comment tag called TODO. To add your own task comment tags, do the following:

The Code Editor includes outlining features you can use to expand and collapse your source code. Use the Edit

The .NET programming languages provide syntax to create a named section of code you can collapse and expand, known as a region directive. To use a region directive, sandwich your code block between a start and end region directive. The syntax for the directive varies, depending on the language you're using.

In Visual Basic, the directive looks like this:

#Region "Description of code block"
'source code here
#End Region

In C#, the directive appears as follows:

#region Description of code block
//source code here
#endregion

Note that C# doesn't require double quotes around the description. Figure 1-7 shows an example of a class using regions to organize the source code.

Figure 1-7. Use a region directive to create collapsible blocks of code.

The Visual Studio Code Editor has a special feature — IntelliSense — that helps you complete syntax while you type. You might recognize IntelliSense as the feature that brings your dot notation to life. When you type a variable's name and then type a period or dot, you get a list of properties and methods that you can use for that variable. The context-aware list of properties and methods is brought to you courtesy of IntelliSense.

IntelliSense is capable of more than listing methods and properties. You can see IntelliSense in action when you

The new IntelliSense features in Visual Studio 2010 take point-and-click code generation to a whole new level. See Chapter 5 in Book III for a demonstration.

Every executable program requires a procedure called Main. The Main procedure is the entry point into your application. In Visual Basic Windows applications, the Visual Basic compiler creates a Main function for you when the Enable Application Framework check box is selected on the Application tab of the project's property pages.

The Movie Collection Starter Kit for C# has a good example of a Main procedure. In the Program.cs source file, you'll find the following Main procedure:

static void Main()
{
  Application.EnableVisualStyles();
  Application.SetCompatibleTextRenderingDefault(false);
  Application.Run(new MainForm());
 }

You must declare variables you wish to use and specify their data type. You can assign a value to the variable when you create it or assign a value in a separate assignment statement.

Visual Basic uses the keyword Dim to declare variables, like this:

Dim variablename as DataType

For example, to declare the variable i as the data type integer in Visual Basic, you type

Dim i As Integer

Comparatively, C# doesn't require any special keywords when declaring variables. You declare variables in C# with the following syntax:

DataType variablename;
int i;

You assign values to variables using the equal (=) operator. For example, to assign the value 7 to the variable i, you'd type this:

i = 7 "(VB)
i = 7; //(C#)

When you read an assignment statement, you say i "gets" 7, not i "equals" 7. In the case of variable assignment, the equal operator is not the same as equality.

You can declare a variable and assign a value in one statement. To combine declaration and assignment in Visual Basic, you type

Dim i As Integer = 7

And in C#:

int i = 7;

See Chapter 2 in Book III for more details on declaring variables and assigning values.

The primary means of organizing code in Visual Basic and C# is class declarations. Your executable code is nested within a class declaration. The following code is an example of a class declaration in Visual Basic:

Public Class Customer
"executable code here
End Class

You use a class using the new keyword, which creates an instance of the class, called an object. You use the object to access the executable code inside the class. For example, to create an object called newCust from the class Customer in Visual Basic, you'd type

Dim newCust As New Customer()

Here's the equivalent statement in C#:

Customer newCust = new Customer();

To call an executable procedure on the newCust object, you use dot notation, as shown here:

newCust.ValidateAddress()

You can consume objects in either language, regardless of what language the object is written in. For example, you can consume a Customer object written in Visual Basic using C#, and vice versa.

See Chapter 3 in Book III for more details on declaring classes and creating objects.

A single line of code is a statement. Both Visual Basic and C# provide syntax that allows you to write multiple statements as a block of code.

Examples where you need to use code blocks include If...Then statements and Try...Catch statements.

C# uses curly braces to encapsulate multiple statements. Visual Basic uses the syntax Procedure...End Procedure. Compare these two If statements for clarification:

"Visual Basic
If flag = True Then
  j = j + 1
  flag = False
End If

//C#
if (flag = true)
{
    j = j + 1;
    flag = false;
}

Executable code is implemented as members of a data type, usually a class. Basically, everything inside a class is a member of the class. A procedure that adds two integers and returns a value is a method. Variables declared for use within the class are fields.

Visual Basic also uses classes and members, but it uses keywords such as Function and Sub to declare a procedure.

See Chapter 3 in Book III for more details on creating members and procedures in classes.

Visual Basic includes an object called My, which you can use to access features related to your application and the .NET Framework. For example, you can use My.Settings to access your application's configuration settings.

You don't have to declare variables or create an instance to use My. You simply type My and a dot in the Visual Basic Code Editor, and a list of available objects appears. Three commonly used My objects are